We propose to participate in "Dietary Intervention in Children with High LDL", with the aim of investigating the feasibility, acceptability, efficacy, and safety of dietary intervention in free-living children, ages 8-10 with elevated LDL-C levels. The study will be done in 3 phases, devoted primarily to planning, then to a feasibility study in 20 children pr clinic lasting 1 year. Based on these results, a full-scale with 3 years followup will be carried out. A cause and effect relationship between plasma cholesterol and coronary heart disease (CHD) has been established, and there is renewed interest in intervening on cholesterol. Recent studies in children have established tracking of cholesterol, a relationship between childhood cholesterol levels and adult CHD, and, preliminarily, the feasibility and safety of dietary intervention to lower LDL. More data is needed, and it is hoped that this study will lead to the wide-spread acceptance of this approach by pediatricians and the public. We propose to recruit a total of 100 children with cholesterol levels between the 90th and 99th percentile and no other major diseases or risk factors, recruited through field capillary blood screening of up to the 30,000 children in the schools and HMO's which have made a commitment to participate. We propose a 2-phase diet, the first consisting of 30% fat with a P:S ratio of 1.5 and 200 mg. per day of cholesterol, and the second containing 30% fat, a P:S ratio of 1.2, and 120 mg. per day of cholesterol. Progression may start with a less restricted diet and move through both phases with a goal of reduction of LDL-C to below the 75th percentile. The intervention will be carried out through a combination of family unit counseling sessions and behaviorally-oriented group sessions, the latter held separately for children and adults. The children's program is based on a social learning model. Followup will be at 4-month intervals for the first year of each intervention phase, with semi-annual assessments in the last 2 years. In addition to lipoproteins, there will be batteries of anthropometric and psychosocial measures taken at least annually. The Principal Investigator will be Norman L. Lasser, M.D., Ph.D., the Project Director of the Newark MRFIT Center and the Hypertension Intervention Trial; Co-PI will be Norman Hymowitz, Ph.D., Co-PI of Newark MRFIT and a member of the AHA's Heart Health in the Young Task Force. Nutrition will be directed by Vera I. Lasser, M.A., R.D., a former MRFIT nutritionist and chief nutritionist in HIT.